Photolithography is a semiconductor manufacturing technique that may be used to generate patterns on the substrate that may be used to form the integrated circuits or electronics devices. Cost and performance improvements in semiconductor devices may be accomplished by increasing device density on a substrate. One approach to achieve higher device density may be to increase miniaturization of features being formed on a semiconductor substrate. Accordingly, new methods or techniques to generate smaller patterns would be desirable.
Self-assembly of block copolymers (BCP) have been used as a tool for decreasing patterned feature sizes using standard photolithography techniques. BCPs may be useful in semiconductor manufacturing because they may form ordered, chemically distinct templates with dimensions of less than 30 nm. The geometry of the template may be manipulated by the molecular weight and composition of the different block types of the copolymer. The template may comprise two or more areas of differing chemical activity that periodically alternate. In one approach, one of the areas of chemical activity may be attractive to one of the block copolymer phases, while the other area of chemical activity may be neutral to both blocks of the BCP. In one instance, the attractive area may force the BCP to align above it, and then the alternate BCP may be forced to align next to this pinned phase. In this way, the block copolymer can be directed to self-assemble in parallel to the pinning guides over large areas of the substrate.
The template may be formed using different organic materials that may be patterned with organic photoresist. In this instance, the patterning process may need to include a removal process or method that increases the selectivity between the exposed and unexposed organic materials on the substrate.